Call for applications – PhD grant:
Quantum transport modeling of nano-transistors
Aix-Marseille University – ETH Zürich
The continuous downscaling of transistors size in CMOS chips has fuelled the impressive growth of the semiconductor industry. However scaling of the CMOS transistors, which have reached nano-dimensions, faces increasing technological and physical problems. For instance, it is widely recognized that quantum effects and inelastic scattering of the electrons due to lattice vibrations (phonons) will be major factors affecting the integration of such devices. Another consequence of size reduction is an important increase of the heat generation. In that context, proper reconsideration of electron-phonon coupling and confinement effects are required for a deep understanding of charge transport phenomena in low dimensional semiconductors.
The aim of the PhD thesis is then to describe self-heating in quantum simulations, by coupling electron and phonon transport equations. More precisely, the student will implement these effects based on the complementary expertise of the two academic partners. The group of ETH Zürich has already implemented atomistic codes to study the influence of self-heating in ultra-scaled Si nanowire transistors [1-2]. This pioneering work has been applied so far to very narrow devices due to numerical issues. On the other hand the group of Aix-Marseille University has developed a “one-shot” approach to treat electron-phonon interactions [3-4]. This promising technique allows reducing significantly the computational burden of the electron transport simulations. The candidate will then extend the “one-shot” approach to the modeling of self-heating in larger nanowire transistors and other quasi-1D architectures.
This subject represents both physical and numerical major challenges. The overall tasks should answer opened theoretical issues but they will also contribute to the development of novel nano-devices.
This call is part of the « AMIDEX Excellence Academy – PhD Collegium » 2014.
AMIDEX is a foundation of the Aix-Marseille University that aims to fund top-level international research and higher education projects (http://amidex.univ-amu.fr/en).
It aspires then to attract the best international PhD students and offers specific services, through joint supervision of thesis.
PhD grant will be funded for a period of three years from the beginning of the academic year 2014-2015. Besides, the operating expenses to implement the jointly supervised thesis are eligible for 2 years (2014/15 and 2015/16).
Eligibility criteria of the applicants:
Applicants must hold a recent master degree in physics or materials science. Expertise in programming would be highly appreciated.
The PhD applicants will have to enroll in a PhD program, through a jointly supervised thesis between Aix-Marseille University and ETH Zürich.
Deadline for application: April 10th, 2014.
For more information: please contact
Dr. Marc Bescond
IM2NP UMR 7334
49, rue Joliot-Curie – BP 146 – Technopôle de Château-Gombert
13384 Marseille Cedex 13 – France
Prof. Dr. Mathieu Luisier
Integrated Systems Laboratory
8092 Zurich, Switzerland
1) R. Rhyner, and M. Luisier, “Self-heating effects in ultra-scaled Si nanowire transistors,” Int. Electron Devices Meet., p. 790 (2013).
2) M. Luisier, “Thermal transport and Matthiessen’s rule in ultra-scaled Si nanowires,” Appl. Phys. Lett. 103, 113103 (2013).
3) M. Bescond, C. Li, H. Mera, N. Cavassilas, and M. Lannoo, “Modeling of phonon scattering in n-type nanowire transistors using one-shot analytic continuation technique,” J. Appl. Phys. 114, 153712 (2013).
4) H. Mera, M. Lannoo, N. Cavassilas, M. Bescond, “Nanoscale device modeling using a conserving analytic continuation technique,” Phys. Rev. B 88, 075147 (2013).